A. Motivation of writing a paper on Roman aqueduct and sewage system.
B. Organizational overview of paper
C. Thesis Statement
(II) Why Sewage and Aqueduct System was required
- Why Sewage system was required.
- Why Aqueduct System was required.
(III) Sewage and Aqueduct Construction
- How Roman sewage system was built.
- How Roman aqueduct System was built.
(IV) Engineer Aspects of the System
- Water level segregation and Filtration System.
- Water Transport System.
- Water Arches and Underground water system.
- Central Sewage System
(V) Possible problems
- Lead Pollution
- Sudden degradation of water quality.
Roman Aqueducts and the Sewer System
Roman Aqueducts are one of the marvels of the ancient world. In fact, it is believed that the Romans were able to build and maintain big cities because of their superior engineering knowledge of water supply and sewage system. Even today, some of the 2,000 year old technologies used by the ancient Romans are in use in the modern day Italy. The technology used by the Romans was lost during the dark period after the fall of the Roman emperor, but the knowledge of that technology is being rediscovered again through archeological excavation and historical accounts. It is a real wonder as how the Romans were able to build such a technologically intensive system 2,000 years back. The study of Roman sewage and water supply system gives us a great insight into one of the first engineering marvels of the world. This paper will primarily discuss the need for a sewage system in ancient Rome and how that need later into an actual system in the subsequent centuries. This paper will further delve deep into the engineering aspects of both the sewage and the water supply system, and some of the problems encountered by the Romans while building the system.
Reasons for the Requirement of Roman Aqueduct
Rome was the first real city of any human civilization. At its peak, the population of Rome reached as high as 1 million people. With so many people huddled together in a small area, sanitation soon became an issue. Before aqueduct came into existence, all the water related demands for latrine, drinking water, bathing and other purposes were fulfilled either from the river Tiber or from nearby lakes. However, both of these resources fast became polluted due to over usage. This brought out the need for a clean water system to cater to the growing needs of the population.
Figure 1: Ancient Roman Building: A dweller dumping his chamber pot on the road and another is properly dumping it in a pot under the staircase. (Hansen 1999)
Furthermore, with the rapid growth of the population and water pollution, diseases from the use of contaminated water escalated. This forced the administration to search for clean and sustainable sources of water supply. Finally, the ancient Romans residing in top floors of a building often nurtured the habit of throwing their waste on the street that often resulted in dropping on a passerby. Although there were some laws against it, the practice was, nevertheless, not uncommon. This was another reason for the need of building a latrine connected to a sewage system.
Sewage and Aqueduct Construction
It is estimated that the first few sewers of the ancient Rome were built in the 8th century BC. At that time, a very basic drainage system was in place to drain marshes and run-offs. During the reign of Etruscan Kings in the 4th Century BC, Cloaca Maxima was built (Hansen 1999). Cloaca Maxima was an initially an open channel central sewage collection and disposal system. It was enclosed during the reign of Augustus in the 1st Century BC. Latrines available at villas used almost the same concept like today. Public latrines, which became popular during the 2nd and 1st century BC, also served the purpose of socialization.
Aqueduct systems came into existence immediately after the innovation of sewage system. A flowing and forceful system of water supply was required to wash away the sewage underground channels to the Cloaca Maxima. The first aqueduct, Appia, was constructed in 312 BC (Hansen 1999). Almost 16 miles long, it brought water from the nearby lakes. However, subsequent aqueducts, Anio Vetus and Marcia, which were constructed during the 3rd Century BC and 2nd century BC, were almost 45 and 60 miles long respectively bringing water from the northern hills. Anio Novus built during the reign of Julius Caesar was one of the best aqueducts of the Roman civilization. Almost 60 miles long, this aqueduct used to provide potable, bath and waste water separately (Hansen 1999). In total, there were 13 main channel aqueducts bringing water from outside to the city of Rome. There were also several sub aqueducts supplying water to the villas of rich people.
Engineering Aspects of the Water and Sewage System
Figure 2: Sedimentation within Aqueduct (Hayes 2013)
There were many engineering aspects of the water system of the ancient Rome. First of all, the water level segregation was not an easy task for the Romans as there was no technology available to treat the water. Water would get transported through aqueducts openly before it reached cities and then would travel into closed tunnels before being supplied to all (Hayes 2013). The first filtration technique put to use by the Romans was the slowing down of the running water. Stagnation of water or slowdown of water in many places ensured that heavy impurities were settled down, and more clean water was transported. However, this created a lot of sedimentation within the aqueducts because of which often the water flow was stopped to clean the sediments to maintain the quality of water (Hayes 2013). The grade of water used to be determined on the basis of the source it was supplied from. For example, the water from Aqua Novus was considered one of the cleanest as the source of the water was the underground springs in the northern mountains and almost the whole aqueduct was enclosed with water not exposed to air (Squires 2013). This water was made available for the rich people for drinking and bathing purposes (Hayes 2013). Lake water was used for bathing and drinking by the commoners.
The main problem in the ancient water transport system was the height. If the water level was at low land, then it was difficult to supply that water to Rome as many parts of Rome were on the hill. As the pumping system was not available, and the manual system to pump water to greater heights was irrational, the ancient Romans built an aqueduct system to keep the water level high from the source to the destination as long as possible.
Figure 3: Different Types of Aqueduct Structures (Hansen 1999)
Most of the starting points of the aqueducts were at high lands of the north. They were often 40 or 50 miles away from the city limits. Aqueducts often passed through low lands. To keep the height of the water intact, multi-tier bridges were constructed in the low land region (Hansen 1999). Similarly, for steep small valleys where there was not enough space to build multi-tier bridges, inverted siphon systems were constructed. For a few underground aqueducts, vertical tunnels were constructed for the inspection and cleaning purposes (Hansen 1999).
Figure 4: A Roman multi-tier Aqueduct (Daw 2011)
Many question the arch type structure of the Roman water system, and the reason for the Romans never using a normal pipe based system, which would have been less costly and more robust, on a continuous wall structure. However, the first reason for the Romans not going for a normal pipe based system was that building a 60 mile long continuous wall would have posed a geographical obstacle to the movement of people and army from one place to another (Daw 2011). On the other hand, arch type structure never blocked a road fully. Also, the ancient Romans had a huge fascination for arch type structure. Long arch type aqueducts not only ensured that the aqueducts were not blocking any road but also enhanced the beauty of the landscape (Daw 2011).
Figure 5: Latrine System in Roman Civilization (NAU 2014)
The Roman sewage system was very basic at the beginning, but as the availability of water to the city increased, the sewage system also developed. Initially, the sewage system consisted of only a few open drainage systems connected to the central sewage reservoir known as the Cloaca Maxima. Cloaca Maxima was connected to all the main sewage drains of the city (NAU 2014). All the wastes collected in Cloaca maxima were disposed of to the Tiber River. The river got polluted in the process, but the city remained clean. During the reign of Augustus Caesar, all the sewage drainage systems were covered using heavy stone structures so that they did not create blockage to the traffic system, and no foul smell could come out of the drains. Latrine seats were wooded, and the latrine hole was directly connected to the sewage drain (NAU 2014). Poor people used pots for latrine, and they used to empty their pots into the sewer. A constant flow of water through the sewage ensured that the waste was washed away with the water to Cloaca Maxima. Only the rich people had personal latrines at home. Even in ancient Rome also, engineers tried to ensure maximum utilization of the available water. Most of the water used in public and private baths was subsequently used as sewage water to clean the waste (NAU 2014). Initial sewage pipes were made of stones, but later constructions used Terra Cota for the sewage pipes.
Problems with the Water and Sewage System
There were some problems in the ancient aqueduct system in Rome. Many a time, underground lead pipes were used inside the city to supply water to baths, private villas and even public water supply points (Squires 2013). Probably, the ancient Romans were not well aware of the bad effects of lead in water. This might have caused an array of health problems for ancient citizens. However, the constant flow of water through the pipes helped a considerable percentage of lead go down in the water. Also, the water supplied in the ancient Rome was mineral rich. Those minerals used to create a layer on the lead pipes. This helped in creating a layer between lead and the water.
Another problem often faced by the early Romans was the sudden drop in the quality of water (Daw 2011). In many cases, it was observed that a sudden change in weather in the hills caused the water quality to drop drastically. In some of the old ancient accounts, there were complaints about muddy water when there was rain in the hilly area.
Roman aqueducts are one of the wonders of the ancient world. Till date it remains so. With the population of Rome growing bigger, the Roman administration understood the importance of water and the sewage system. They quickly understood the importance of building a sewage system, transport system and water system in order to sustain a big city like Rome. As early as the 8th century BC, the Romans started building the sewage system. Aqueducts were first introduced in Rome in the 4th Century BC. Aqueducts were the lifeblood for Rome. Still many aqueducts are used for supplying water to Rome.
Northern Arizona University (NAU). The Evolution of Sewage Treatment. Onsite Wastewater Demonstration Project. 2014. Web. 17 Mar 2014. <http://www.cefns.nau.edu/Projects/WDP/resources/History/History.htm>
Hayes, Jeffrey. Facts and Details (F&D). Infrastructure, Communication and Energy in Ancient Roman Civilization. 2013. Web. 17 Mar 2014. <http://factsanddetails.com/world/cat56/sub369/item2053.html>
Squires, Nick. Lasers and robots explore ancient Rome’s hidden aqueducts. The Telegraph. 26 Oct 2013. Web. 17 Mar 2014. <http://www.telegraph.co.uk/news/worldnews/europe/italy/10406557/Lasers-and-robots-explore-ancient-Romes-hidden-aqueducts.html>
Daw. History on Roman Baths,Aquaducts, and the Goddess Sulis Minerva. Sodahead. 08 Apr 2011. Web. 17 Mar 2014. < http://www.sodahead.com/united-states/history-on-roman-bathsaquaducts-and-the-goddess-sulis-minerva/question-1659781/?link=ibaf&q=&esrc=s>
Hansen, R.D. Water and Wastewater Treatment Systems in Imperial Rome. WaterHistory.org. 1999. Web. 17 Mar 2014. < http://www.waterhistory.org/histories/rome/t1.html#REF>
Gill, N.S. Aqueducts, Water Supply and Sewers in Ancient Rome. Web. 17 Mar 2014. <http://ancienthistory.about.com/od/aqueducts/p/RomanWater.htm>